Pole bean row orientation

shuffles_gwFebruary 6, 2013

Any thoughts on east/west versus north/south pole bean row orientation? I would have thought north/south would be most productive. This study indicated east/west was much more productive. What has been your exprience? I need to decide soon as I am getting ready to plant.

I'm having trouble wrapping my mind around that math. Either the experiment has not been fully described in the article (which certainly seems to be true) and/or the math - and the results - are questionable.

The narrative suggests that the N-S planting suffered more wind damage than the E-W row, which may have contributed to the disparity in yield. Still, the difference seems to be too extreme to have been caused by that alone. In rows of that length, there may have been other factors involved; varying soil fertility, soil sloping (with corresponding differences in soil moisture), shading by trees, etc. My rural plot is only 100' square, but it is high dry clay on one side, and low wet silt on the other... I could not reasonably compare plants grown under such dissimilar soil conditions.

Nor, while multiple rows are described, is there is any mention of row spacing. In adjacent rows of equal spacing, I would expect pole beans in N-S rows to yield slightly less, since they would be shaded by neighboring rows for part of the day. E-W rows would get full sun for most of the day. For single rows, N-S rows would get 1/2 day sun on one side, then 1/2 day sun on the other; E-W rows would get full sun for most of the day, but only on one side of the plants.

For single rows in full sun, I have not seen any observable differences; several of my highest dry bean yields were in rows of N-S orientation. The "Mottled Sieva" pole lima that I grew last year had rows in both E-W & N-S orientation, and while I did not measure their yields separately, there was no observable difference between them.

Thanks for the input. Agreed, that news article lacked some important details. I noticed that they planted in Delaware just after the summer Solstice. The sun would have beeen high in the sky at that time, shining on both sides of the east/west rows. I am planting soon, long before even Equinox. Although it is warm here, the sun is low in the sky, and the beans will be finished well before Solstice. I have decided on six north/south rows instead of three east/west rows. That way, all the rows should get about the same amount of sun.

I did an evaluation of in row shading effects a few years ago. Long story short, the north/south orientation ALWAYS loses. You get best results by orienting rows by the amount of your latitude from true east/west. For example, I am at 36 degrees north latitude, therefore I will get best results by lining up my rows from southeast to northwest at about 36 degrees. This is only true for plants that grow significantly vertical. Sweet potatoes for example do not show such effects.

Thank you Wertach. That is interesting. If rows were 3-4 feet apart, it seems like orientation might make more difference but at 6 feet I thought it might not matter as much. Oh well. Looks like E-W or lined up with the latitude degrees wins.

Nice info in this post! Thank you! We placed 8 foot high trellises 20 feet long, about 6-7 feet apart from each other. To be totally honest with you, now I wish we had spaced the trellises 10 feet or more apart from each other!

Do you know why? We live in Central California, and when the late fall arrives, the trellis on the east, will nearly completely block the sun for next trellis, and on and on and on with each trellis.

This winter, I carefully studied the shade/sun patterns and discovered that if I spaced the trellises 10 or more feet apart, from east to west, then, even when the sun rises lower each day, each trellis receives ample amount of sunshine.